This invention relates to newly identified polynucleotides, polypeptides encoded by such polynucleotides, the use of such polynucleotides and polypeptides, as well as the production of such polynucleotides and polypeptides. More particularly, the polypeptide of the present invention is choline acetyltransferase, sometimes hereinafter referred to as xe2x80x9chChATxe2x80x9d. The invention also relates to inhibiting the action of such polypeptides.
A human choline acetyltransferase gene has been isolated from the human brain (McGeer P. L. et al., Life Sci., 34:2319-2338 (1984)). Choline acetyltransferase is specifically expressed in cholinergic neurons. Choline acetyltransferase is an enzyme which catalyzes a reaction which yields the neurotransmitter acetylcholine. Although choline acetyltransferase expression has been found in both neurons and certain non-neuronal tissues, such as placenta (Schuberth, J., Biochim. Biophys. Acta, 122:470-481 (1966)) and spermatozoa (Ibanez, C. F. and Persson, H., Eur. J. Neurosci., 3:1309-1315 (1991)), the expression of this enzyme is largely limited to certain neurons.
The 5xe2x80x2 flanking region of the human choline acetyltransferase gene differs from the rodent gene in that the rodent gene has a xe2x80x9cTATAAxe2x80x9d box consensus sequence upstream of the transcription start site, but no such element is found in the human gene. The rodent gene also differs in that it contains at least three promoters and the sequence corresponding to only one of the promoters, the M type, is found in the human gene (Hersh, L. B., et al., J. Neurochem., 61:306-314 (1993)).
The control of motor behavior constitutes one of the most important functions of the central nervous system. Numerous regions of the brain are involved in this process that is integrated ultimately in the motor neurons of the spinal cord, the xe2x80x9cfinal common pathxe2x80x9d in the control of movement. These neurons, which lie in the ventral horn, exhibit a cholinergic phenotype and, therefore, express choline acetyltransferase. Choline acetyltransferase is a specific marker of the cholinergic system.
In accordance with one aspect of the present invention, there is provided a novel mature polypeptide which is hChaT, as well as biologically active and diagnostically or therapeutically useful fragments, analogs and derivatives thereof.
In accordance with another aspect of the present invention, there are provided isolated nucleic acid molecules encoding hChaT, including mRNAs, DNAs, cDNAs, genomic DNA as well as biologically active and diagnostically or therapeutically useful fragments, analogs and derivatives thereof.
In accordance with yet a further aspect of the present invention, there is provided a process for producing such polypeptide by recombinant techniques which comprises culturing recombinant prokaryotic and/or eukaryotic host cells, containing a hChaT nucleic acid sequence, under conditions promoting expression of said protein and subsequent recovery of said protein.
In accordance with yet a further aspect of the present invention, there is provided a process for utilizing such polypeptides, or polynucleotide encoding such polypeptide for therapeutic purposes, for example, to treat amyotrophic lateral sclerosis (ALS), Alzheimer""s Disease, familial disautonomia, Huntington""s Disease, mental retardation, memory loss, myasthenia gravis and other disorders known to involve the cholinergic system or affect its pathways and nerves in the body.
In accordance with another aspect of the present invention there are provided nucleic acid probes comprising nucleic acid molecules of sufficient length to specifically hybridize to hChaT sequences.
In accordance with yet a further aspect of the present invention, there are provided antibodies against such polypeptides.
In accordance with another aspect of the present invention there is provided a method of diagnosing a disease or a susceptibility to a disease, related to a mutation in hChaT nucleic acid sequences and the protein encoded by such nucleic acid sequences, for example, Alzheimer""s disease.
In accordance with yet another aspect of the present invention, there are provided antagonists to such polypeptides, which may be used to inhibit the action of such polypeptides, for example, in the treatment of Parkinson""s Disease and accidental overdoses with various pharmaceuticals and contamination by toxins.
These and other aspects of the present invention should be apparent to those skilled in the art from the teachings herein.